Atec PA-141 User Manual

PA-141

abworks Inc.

L

High quality audio power for vibration test systems.

Linear Power Amplifier

GENERAL DESCRIPTION

The Labworks PA-141 Linear Power Amplifier is a high
quality, air-cooled, direct-coupled audio amplifier primarily
intended for use with vibration systems. Although this
amplifier has been designed to directly drive low impedance
loads, it can be used in any application requiring continuous
duty, high quality, audio power.

There are two operational modes. The amplifier can be
used as either a wide-band, highly damped voltage source,
or as a high impedance current source. DC and AC coupled
signal inputs are provided.

In order to insure long term reliability, the PA-141 features
protection from both over current and over temperature.

FEATURES

■

Linear output stage provides low
noise and distortion.

■

Automatic over temperature and over
current protection.

■

Direct coupled input and output allows
DC operation.

■

External interlock circuitry.

Full interlock circuitry is also included. Peak voltage and RMS
current bar graphs monitor output conditions.

Optional, internal DC field power supplies are available for
use in conjunction with Labworks Shakers. These options
provide the convenience of a single chassis power source,
as well as fully integrated power-up and cooling interlock
circuitry with the power amplifier. Switched 115 Vac power
is provided for shaker cooling blower and control instrument
requirements.

The PA-141 is designed for standard 19 in. rack mounted
installation and can be operated on 100, 120, 200, 220 or
240V, 48 to 62 Hz power.

■

Two operational modes, voltage or
current source.

■

Optional internal shaker field supplies.

2950 airway ave., a-16, costa mesa, ca 92626 • [phone] • fax [phone]

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10

20

30

40

50

60

510152025

8Ω

4Ω

2Ω

1Ω

Volts

rms

Amps

rms

Output Capability

1 K

300

100

30

10

Ω

30

100 300 1000

-2.5

-5.0

dB

0.0

Hz

Output
Impedance

Current
Response

Current Source Mode Performance

0

0

-2

-2

-4

-4

0.1 1.0 10 100 1K 10K 30K.01

dB

dB

DC input

AC input

Hz

Voltage Source Mode Response Performance

0

0

M

A

X

.

C

O

N

T

.

D

I

S

S

I

P

A

T

I

O

N

MAX. CONT.

OUTPUT CURRENT

abworks Inc.

2950 airway ave.
a-16, costa mesa, ca 92626 [phone]

PA-141 SPECIFICA TIONS*

Output Voltage (continuous)

10 Hz to 20 KHz

open circuit 62.0 V rms
4Ω load 49.0
2Ω load 40.0
1Ω load 20.0

DC to .1 Hz

open circuit 87.5 Vdc/pk
4Ω load 69.0
2Ω load 56.5
1Ω load 28.0

Random Voltage Output

2.5 sigma peak volts
open circuit 36.0 V rms
4Ω load 30.0
2Ω load 28.0
1Ω load 20.0

3.0 sigma peak volts
open circuit 30.0 V rms
4Ω load 25.0
2Ω load 23.0
1Ω load 20.0

Maximum continuous dissipation

Ambient Temp = 40°C 900W

Frequency response (DC coupled input)

DC to 10 KHz -0.6 dB
DC to 20 KHz -2.5
AC coupling @ 1.0 Hz -0.5

Slew rate 6.0 V/µsec
Harmonic distortion

(10V, DC-10k) <0.65% @ 1Ω

Signal/noise ratio

(ref 50V out) 100 dB minimum

Input impedance

DC coupled 10 kΩ
AC coupled 47 uF in series with 10 kΩ

DC offset

Voltage mode 5 mV max
Current mode 3 mA max

Voltage mode gain 96 (40 dB) max
Current mode gain 22 Amps/Volt max
Voltage source regulation <0.1 dB (

Current source regulation <0.1 dB (0-2Ω load,
Front panel metering

Type (2) 19 seg. horiz. bar graphs
Scale

Voltage 0-72V pk
Current 0-20 A rms

Resolution

Peak voltage 5% of full scale
True rms current 5% of full scale
Accuracy (voltage & current) ±5% absolute

50 450
60 0

30 Hz/20 V rms)
30 Hz/10 A rms)

∞ - 2Ω load,

Front panel indicators

Internal power, interlock trip

Front panel controls Power switch, mode switch,

gain adjust

Interlock circuit

Type Logic <1 Vdc or

switch open = fault
Response time 3 ms. max
Action Output drives to nil
Reset Gain pot full down or

> 1.5V @ RST
Indicator

Flashing front panel "Trip" light

Cooling 2-speed fan

Noise level: low/high speed <53 dB/<67 dB

(switches @ approx. 1/2 diss.)

Self protection

Over current, over temperature

Line protection

Dual circuit breaker 15A

115 Vac convenience output Std. Duplex (USA)

PA-141 3A
PA-141-127 20A
PA-141-140 12A

Optional DC shaker field power supplies

141-127 32V, 28A DC Nom.
141-140 12V, 12A DC Nom.

Input power

PA-141 2,000 VA max
PA-141-127 or -140 3,000 VA max
Voltage

100, 120, 200, 220 or 240 Vac
Frequency 48 to 62 Hz

Dimensions 7.0" H x 19" W x 17" D
Weight

PA-141 (PA-141-127 or-140) 48 lbs (73 lbs)

*Specifications subject to change. Consult factory for latest specifications.

PERFORMANCE GRAPHS